We've shown you how to put on sunscreen, but what about the sunscreen's effectiveness? Many question which sunscreen they should buy and whether or not it is effective, so read on to find out what tips you should follow in order to select the best one.

When purchasing sunscreen, it is always best to stick with a broad spectrum lotion that protects against UVA and UVB rays. It is also important to stick with a sunscreen that has a SPF of 30 or more and is water-resistant. The higher the SPF the better for those with fairer skin. These are the three most important factors that determine whether or not your sunscreen is effective, however read on for more helpful tips.

Another important fact to remember is that sunscreens on their own are far more effective than when combined with cosmetics. Many cosmetics offer a base element of sunscreen protection, however it is usually a low SPF factor of 15 and is not broad spectrum. Your best bet is to start your makeup routine with a base layer of regular sunscreen, then follow with your makeup coverage once the sunscreen has been absorbed. It is important that the sunscreen has been absorbed into the skin before putting on cosmetics, as makeup is designed to only sit on top of the skin.

A second reason cosmetic SPF is not effective, is due to the fact that we simply do not use enough of it, or re-apply as often as we should. Consider this - if someone applies a full face of makeup on in the morning, will they do they same in the afternoon? Highly unlikely as most will assume they can go the entire day with what they applied in the morning. Unfortunately this is where cosmetic sunscreen falls short. It is important to re-apply often and correctly, as many people may not include the ears or neck when layering on cosmetics such as foundation.

What about the expiration date? Sometimes we may buy a few different bottles of sunscreen and after a particularly dark winter we may forget about using them. While you should definitely be wearing sunscreen in winter (read why here), it is common to wonder if sunscreen really does 'go bad'. In general if you have kept the sunscreen in a cool and dry storage space, it should still be effective up to 6 months past its expiration date. If you have stored it somewhere that receives a lot of sunlight, heat, water, or exposure to the elements, you definitely need to buy new sunscreen.

According to the Skin Cancer Foundation, 'Expiration dates are often stamped on sunscreen containers to specify the time limit for a product’s stability and efficacy. For optimal sun protection as well as texture, stability, and sterility, use the sunscreen prior to the date listed. If you can’t find a date on a new tube or bottle, write the month and year you purchased it in permanent marker on the tube.'A good tip to be sure, and please remember to store sunscreen in a cool and dry area.

​Please let us know about any questions you may have regarding your sunscreen in the comments below.